Synthesis of chitosan beads as boron sorbents

Abstract

Parameters, such as pH, temperature, initial boron concentration, adsorbent dosage, and ionic strength, affecting boron adsorption onto chitosan beads were examined in this study. The following values were obtained as the optimum conditions in our studied ranges: pH 8.0, temperature ¼ 308 K, amount of chitosan beads ¼ 0.15 g, initial boron concentration ¼ 4 mg L À1, and ionic strength ¼ 0.1 M NaCl]. The adsorption kinetics were also examined in terms of three kinetic models: the pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. The pseudosecond-order kinetic model showed very good agreement with the experimental data. Intraparticle plots seemed to have two steps and indicated multilinearity. Equilibrium data were evaluated with nonlinear and linear forms of the Langmuir and Freundlich equations. The experimental data conformed to the Freundlich equation on the basis of the formation of multilayer adsorption. To characterize the synthesized chitosan beads, we used Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) analyses. As shown by FTIR analysis, the boron species may have interacted with the NH 2 groups on chitosan. Microparticles of about 5 lm appeared in the SEM micrographs of the chitosan beads. V C 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: [657][658][659][660][661][662][663][664][665] 2011

Boron Removal by Adsorption on Cobalt(II) Doped Chitosan Bio-composite

“…The n value greater than 1 means an S-type isotherm and also corresponds to physical adsorption [46]. Similarly, Bursali et al [25] found that the Freundlich equation provided better conformity than the Langmuir equation: experimental data of boron adsorption on chitosan beads confirmed to the Freundlich equation on the basis of the formation of multilayer adsorption. Differently, the Langmuir equation gave the best fit of the experimental data for composite [chiNi(II)], made of chitosan and nickel(II) by Demey et al [33].…”

“…Comparing of the maximum adsorption capacities of chitosan found in the literature, Co-CTS composites have a capacity of the same order of magnitude as other adsorbents, e.g. Bursali et al [25] calculated the adsorption capacity of boron on chitosan beads about 2.5 mg/g at 25 °C. Although composite [chiNi(II)], made of chitosan and nickel(II) hydroxide [33] and oxide/ hydroxide-based nanoparticles (NanoFe) [47] present better q, they have a great disadvantages.…”

“…The effects of temperature, pH, adsorbent dosage, time, and ionic strength on adsorption were examined. Adsorption of boron species onto the chitosan beads without modification occurred with physical forces and characterised with not high enough capacity [25]. The researchers' attention has been given to the functionalized chitosan-based materials.…”

Evaluation of the Interaction between Borate Ions and Nickel–Aluminum Complex Hydroxide for Purification of Wastewater

“…[24][25][26][27] In addition, the reported adsorption capacities of various adsorbents are shown in Table 2. 18,26,[28][29][30][31] The amount of borate ion adsorbed on NA11 was greater than that of most other adsorbents. Therefore, NA11 would be useful for the adsorption of borate ions from aqueous solutions.…”

Biological Effects and Extraction Processes Used to Obtain Marine Chitosan

“…They can be obtained via electrospinning of chitosan/agarose solution to reduce the viscosity of the blend (Elsabee et al 2012). Chitosan can also be used for the absorption of anions, as boron species, that may interact with the NH 2+ groups of chitosan at basic pH (Bursali et al 2011;Wei et al 2011).…”